The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Many audio and video applications are made digitally available to end users by a service provider. When a service provider provides media content to an end user, the service provider would like to ensure that the media content is consumed only by that end user and not by others, such as neighbors. Limiting media content to a given premises is sometimes referred to as localization.
Referring now to FIG. 1, a functional block diagram of a media localization system according to the prior art is presented. A media server 102 receives content from a service provider (not shown) and communicates with networking devices 104. A media client 106 communicates with the networking devices 104. In order for the media server 102 to determine whether to allow the media client 106 to access media content, the media server 102 sends a delay request frame, such as a ping message, to the networking devices 104.
Each of the networking devices 104 forwards the delay request frame to a subsequent one of the networking devices 104 until the delay request frame is sent to the media client 106. The media client 106 responds with a delay response frame, which is forwarded through the networking devices 104 to the media server 102.
The media server 102 can then estimate the physical distance between the media server 102 and the media client 106 by analyzing the time delay between the delay request frame and the delay response frame. This time delay must be adjusted by removing the typical delay experienced by the frames within each of the networking devices 104. Adjustment is problematic, however, because delays may vary greatly depending upon the current state of the network.
Referring now to FIG. 2, a functional block diagram of a simple computer network is depicted. The network includes first and second PCs 150 and 152, each containing a network interface, 154 and 156, respectively. The network interfaces 154 and 156 communicate with a networking device, such as a switch 158. The network interfaces 154 and 156 may include cable testing technology, such as Virtual Cable Tester™ from Marvell. Using cable testing, the network interfaces 154 and 156 can determine whether there are any wiring faults between them and the switch 158.